I am trying to get my Arduino Duemilanove to read/write to an SD card. I have a TinkerIt ethernet board, with solderpads for an SD slot. Since I assumed those pads had to be connected to something, I've soldered an SD slot to the ethernet shield. Plugged in an SD card, turned on the power.. LEDs turned on and no smoke escaped XD

To actualy read or write to the card, I've at first used the default 1.01 SD library. My code:

Yes, this is the ReadWrite example provided with the SD library When I run this code, it say "Initialization failed!". Hence SD.begin(4) failed. I also tried ports 8 and 10, but since this is an ethernet port I believe 4 is the correct port.

I have tripple checked AND resoldered the SD slot. I have tested the setup with a 8GB formatted at FAT32 and a 2GB SD card formatted at FAT16 , both formatted at FAT32. I am aware FAT16 is prefered, but it should still work with FAT32.Unfortunatly I can not find any decent information about the Tinker It ethernet shield, but it is based on a Wiznet W5100.

Using the SD slot does make the W5100 chip warm up, but it does not become hot. I can still use the ethernet module, so the chip is still alive and well.

Also, I do notice a lot of ethernet shields have Micro-SD slots, leaving a couple of solderpads unused. Since I am using a regular SD card, does this make a difference?

Does anyone know where to look for as to why the SD card can not be read?Thanks

Well, this explains a lot.. I have measured all SD slot pins. Normally the DataIn, DataOut and Clock pins should be connected to the SPI ports of the Arduino (11,12,13). Instead they are wired to the following Arduino pins. CS, pin 6 DataIn, pin 8 DataOut, pin 3 Clk, pin 9